Explain about the course of events during spontaneous blinking.

Course of Events during Spontaneous Blinking:

Given ate the course of events which take place in the following order. The process is also responsible for drainage of tear film across the cornea to drab ultimately into lacrimal apparatus.

Function of blinking movements in the eyelid

The function of blinking movements can be categorised into voluntary and involuntary with sub-categories as spontaneous and reflex. A voluntary blink is a coordinated closure and opening movement carried out in both eyes. The muscles used in this action are the oribtal and palpebral portions of the orbicularis. An involuntary blink is composed of spontaneous and reflex types. The spontaneous blink occurs without any obvious external stimulus.

Its function in addition to protection is to reform and redistribute the precorneal tear film. The rate for a spontaneous blink is about 12-20 times minute and the opening phase is always greater than the closing phase. The effect of a blink on vision is the discontinuity of the visual sensation. The reflex type of involuntary blink occurs as a coordinated closing and opening movement of the eyelids that occur as a reflex in response to a direct stimulus (can be tactile, optic, auditory or stretch).